Pregnant Kate Middleton will reportedly go on maternity leave as early as June 13.

According to an anonymous source who spoke to The Mirror on Sunday, the Duchess will take a break from her royal duties to prepare for the baby. 

"Kate has really enjoyed her job and wanted to work as close to the birth date as possible," the source said.

June 13 will mark Kate's "last official solo engagement," when she is scheduled to christen a cruise ship. 

"She takes her royal role very seriously and is looking forward to taking up her duties when her maternity leave has finished," the source added. 

The Huffington Post reported that it is royal tradition for mothers with newborns to take time off from their duties, as Kate is reported to do, although Princess Diana broke the tradition when 8-month-old Prince William accompanied her along a royal tour of Australia in 1983. 

"The Duchess will give birth at some point in 2013 and it would be unusual for her to travel in the couple of months after that," a source said last December.

"No overseas tour has yet been planned for next year, and obviously the arrival of the baby will have an effect on the Duchess's diary.

The report regarding Kate's maternity leave has fueled more speculation to her due date. 

Enstars noted earlier that sources close to the couple said the Duchess is expecting to give birth during the second week of July.

"Some of Kate and William's closest pals were at a barbecue hosted by a family friend of the Royals recently. They were all discussing the fact that Kate's baby is due to be born on July 13. Everyone was very excited," a source said. 

However, later reports indicated that Kate's mother, Carole Middleton said that at her grandchild will be a Leo, which means the due date could range anywhere between July 24 and Aug 23.

The couple has yet to confirm the baby's gender. 

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